package com.infore.gateway.main.utils;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;

public class Aes {
    //密钥 (需要前端和后端保持一致)
    private static final String KEY = "SMARTBI_SIGN_KEY";

    public static void main(String[] args) throws Exception {

        //1587108388
        String encryptPassword = "qPDdAWzFO4Nr+NdDliik75YjfWP8clycIqpZm5iVuAI=";
        System.out.println("解密前：" + encryptPassword);  
        String decryptPassword = Decrypt(encryptPassword, KEY);
        System.out.println("解密后：" + decryptPassword);
        //a4d7395974a97dfbfff77af29cd343a6
        String encrypt = Encrypt("SMART_BI_SIGN_" + "1587107835", KEY);
        System.out.println("======encrypt======"+encrypt);


        String sign = "SMART_BI_SIGN_" + "1587107835";
        MessageDigest digest = MessageDigest.getInstance("Md5");
        byte[] digest1 = digest.digest(sign.getBytes());
        System.out.println("========="+new String(digest1));
        System.out.println("========="+"a4d7395974a97dfbfff77af29cd343a6");
    } 
    
    /**
     * 加密    
     * @param sSrc
     * @param sKey
     * @return
     * @throws Exception
     */
    public static String Encrypt(String sSrc, String sKey) throws Exception {  
        if (sKey == null) {  
            System.out.print("Key为空null");  
            return null;  
        }  
        // 判断Key是否为16位  
        if (sKey.length() != 16) {  
            System.out.print("Key长度不是16位");
            return null;  
        }  
        byte[] raw = sKey.getBytes("utf-8");  
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");  
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");//"算法/模式/补码方式"  
        IvParameterSpec iv = new IvParameterSpec(sKey.getBytes());//使用CBC模式，需要一个向量iv，可增加加密算法的强度  
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);  
        byte[] encrypted = cipher.doFinal(sSrc.getBytes());  
        return new Base64().encodeToString(encrypted);//此处使用BASE64做转码功能，同时能起到2次加密的作用。  
    }
    
    /**
    * 解密  
    * @param sSrc
    * @param sKey
    * @return
    * @throws Exception
    */
    public static String Decrypt(String sSrc, String sKey) throws Exception {  
       try {  
           // 判断Key是否正确  
           if (sKey == null) {  
               System.out.print("Key为空null");  
               return null;  
           }  
           // 判断Key是否为16位  
           if (sKey.length() != 16) {  
               System.out.print("Key长度不是16位");  
               return null;  
           }  
           byte[] raw = sKey.getBytes("utf-8");  
           SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");  
           Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");  
           IvParameterSpec iv = new IvParameterSpec(sKey.getBytes());  
           cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);  
           byte[] encrypted1 = new Base64().decode(sSrc);//先用base64解密  
           try {  
               byte[] original = cipher.doFinal(encrypted1);  
               String originalString = new String(original,"utf-8");  
               return originalString;  
           } catch (Exception e) {  
               System.out.println(e.toString());  
               return null;  
           }  
       } catch (Exception ex) {  
           System.out.println(ex.toString());  
           return null;  
       }  
    }

}